Whether you want to track every purchase you make at the grocery, the number of hours you spent at the gym, or every book you've ever read, do so with the charmingly simple data visualization app Mem:o (Free). It allows you to view each snippet of data, or memo, as a circle, with bits of text and numbers to help add meaning. You then collect each of these related memos onto a board or calendar, letting you see all your information at once. Share your collections with friends on Facebook or Twitter, or just hoard them all and reflect back some day.